Clinical translation of tissue-engineered advanced therapeutic medicinal products is hindered by a lack of patient-dependent and independent in-process biological quality controls that are reflective of in vivo outcom...Clinical translation of tissue-engineered advanced therapeutic medicinal products is hindered by a lack of patient-dependent and independent in-process biological quality controls that are reflective of in vivo outcomes.Recent insights into the mechanism of native bone repair highlight a robust path dependence.Organoid-based bottom-up developmental engineering mimics this pathdependence to design personalized living implants scaffold-free,with in-build outcome predictability.Yet,adequate(noninvasive)quality metrics of engineered tissues are lacking.Moreover,insufficient insight into the role of donor variability and biological sex as influencing factors for the mechanism toward bone repair hinders the implementation of such protocols for personalized bone implants.Here,male and female bone-forming organoids were compared to non-bone-forming organoids regarding their extracellular matrix composition,transcriptome,and secreted proteome signatures to directly link in vivo outcomes to quality metrics.As a result,donor variability in bone-forming callus organoids pointed towards two distinct pathways to bone,through either a hypertrophic cartilage or a fibrocartilaginous template.The followed pathway was determined early,as a biological sexdependent activation of distinct progenitor populations.Independent of donor or biological sex,a cartilage-to-bone transition was driven by a common panel of secreted factors that played a role in extracellular matrix remodeling,mineralization,and attraction of vasculature.Hence,the secreted proteome is a source of noninvasive biomarkers that report on biological potency and could be the missing link toward data-driven decision-making in organoid-based bone tissue engineering.展开更多
Inflammation plays an essential role in the development of atherosclerosis. The initiation and growth of atherosclerotic plaques is accompanied by recruitment of inflammatory and precursor cells from the bloodstream a...Inflammation plays an essential role in the development of atherosclerosis. The initiation and growth of atherosclerotic plaques is accompanied by recruitment of inflammatory and precursor cells from the bloodstream and their differentiation towards pro-inflammatory phenotypes. This process is orchestrated by the production of a number of pro-inflammatory cytokines and chemokines. Human arterial intima consists of structurally distinct leaflets, with a proteoglycan-rich layer lying immediately below the endothelial lining. Recent studies reveal the important role of stellate pericyte-like cells(intimal pericytes) populating the proteoglycan-rich layer in the development of atherosclerosis. During the pathologic process, intimal pericytes may participate in the recruitment of inflammatory cells by producing signalling molecules and play a role in the antigen presentation. Intimal pericytes are also involved in lipid accumulation and the formation of foam cells. This review focuses on the role of pericytelike cells in the development of atherosclerotic lesions.展开更多
Clinical pharmacology aims to predict drug-related effects based on compound and population specific pharmacokinetics(PK, concentration-time), and pharmacodynamics(PD, concentration-effect). Consequently, dosing needs...Clinical pharmacology aims to predict drug-related effects based on compound and population specific pharmacokinetics(PK, concentration-time), and pharmacodynamics(PD, concentration-effect). Consequently, dosing needs to be based on the physiological characteristics of the individual patient. Pregnancy and early infancy hereby warrant focused assessment. The specific characteristics of both subpopulations will be illustrated based on observations on intravenous(iv) paracetamol PK and PD collected in these specific populations. At delivery, there is a significant higher paracetamol clearance(+ 45%, L/h) when compared to non-pregnant observations. This higher clearance is in part explained by a proportional increase in oxidative metabolite production, but mainly an increase in glucuronidation. When focusing on PD, an association between maternal paracetamol exposure and atopy in infancy and fetal gastroshizis has been reported. In early infancy, paracetamol clearance is significantly lower and mainly depends on size(weight 0.75), while also the distribution volume is higher(L/kg). Reports on hepatic tolerance, haemodynamic stability and impact of bodytemperature have been published while the concentration effect profile for analgesia seems to be similar between neonates and children. Similar to maternal exposure, there are reports on the association with atopy. Studies on the use of paracetamol to close the patent ductus arteriosus are ongoing. At least, these observations provide evidence on the need to study commonly administered anesthetics in such specific subpopulations with specific focus on both population specific PK and PD to further improve patient tailored pharmacotherapy.展开更多
Decellularized organs and tissues are emerging within the field ofregenerative medicine to meet the growing demand for organand tissue transplantation. Quality control of these acellular matrices prior to transplantat...Decellularized organs and tissues are emerging within the field ofregenerative medicine to meet the growing demand for organand tissue transplantation. Quality control of these acellular matrices prior to transplantation is of paramount importance to ensure the absence of an adverse reaction. In particular, thoroughevaluation of the DNA content is essential but also poses technical challenges. Therefore, in this study, we compared differentmethods for quantitative and qualitative evaluation of DNA content in native and decellularized skeletal muscle tissue to identifystrengths and weaknesses for each. Histological analysis revealedthat Feulgen staining is more sensitive and robust than the commonly used hematoxylin–eosin and 40,6-diamidino-2-phenylindole staining for detection of remaining nuclear material.Furthermore, gel electrophoresis allowed to identify the quality and length of remaining DNA fragments. The results of the quantitativeanalysis indicated that direct measurement of DNA content in tissue lysates is preferred over silica-based extraction methods, since thelatter resulted in the loss of small DNA fragments during extraction. Moreover, a weight loss correction factor should be implementedto take into account the impact of the decellularization on the extracellular matrix. With regard to the detection method, the resultsrevealed that a fluorescence-based approach is more accurate than the use of UV/VIS absorbance. Through combination of the proposedmethods, it should be possible to achieve a more standardized evaluation of novel acellular matrices in terms of DNA content and toenhance the predictability of clinical success.展开更多
Drugs are very strong tools used to improve outcome in neonates. Despite this fact and in contrast to tailored perfusion equipment, incubators or ventilators for neonates, we still commonly use drug formulations initi...Drugs are very strong tools used to improve outcome in neonates. Despite this fact and in contrast to tailored perfusion equipment, incubators or ventilators for neonates, we still commonly use drug formulations initially developed for adults. We would like to make the point that drug formulations given to neonates need to be tailored for this age group. Besides the obvious need to search for active compounds that take the pathophysiology of the newborn into account, this includes the dosage and formulation. The dosage or concentration should facilitate the administration of low amounts and be flexible since clearance is lower in neonates with additional extensive between-individual variability. Formulations need to be tailored for dosage variability in the low ranges and also to the clinical characteristics of neonates. A specific focus of interest during neonatal drug development therefore is a need to quantify and limit excipient exposure based on the available knowledge of their safety or toxicity. Until such tailored vials and formulations become available, compounding practices for drug formulations in neonates should be evaluated to guarantee the correct dosing, product stability and safety.展开更多
Mesoangioblasts(MABs)are vessel-associated stem cells that express pericyte marker genes and participate in skeletal muscle regeneration.Molecular circuits that regulate the myogenic commitment of MABs are still poorl...Mesoangioblasts(MABs)are vessel-associated stem cells that express pericyte marker genes and participate in skeletal muscle regeneration.Molecular circuits that regulate the myogenic commitment of MABs are still poorly characterized.The critical role of bone morphogenetic protein(BMP)signalling during proliferation and differentiation of adult myogenic precursors,such as satellite cells,has recently been established.Weevaluated whether BMP signalling impacts on the myogenic potential of embryonic and adult MABs both in vitro and in vivo.Addition of BMP inhibited MAB myogenic differentiation,whereas interference with the interactions between BMPs and receptor complexes induced differentiation.Similarly,siRNA-mediated knockdown of Smad8 in Smad1/5-null MABs or inhibition of SMAD1/5/8 phosphorylation with Dorsomorphin(DM)also improved myogenic differentiation,demonstrating a novel role of SMAD8.Moreover,using a transgenic mouse model of Smad8 deletion,we demonstrated that the absence of SMAD8 protein improved MAB myogenic differentiation.Furthermore,once injected into a-Sarcoglycan(Sgca)-null muscles,DM-treated MABs were more efficacious to restore a-sarcoglycan(aSG)protein levels and re-establish functional muscle properties.Similarly,in acute muscle damage,DM-treated MABs displayed a better myogenic potential compared with BMP-treated and untreated cells.Finally,SMADs also control the myogenic commitment of human MABs(hMABs).BMP signalling antagonists are therefore novel candidates to improve the therapeutic effects of hMABs.展开更多
基金financed by the Hercules Foundation(project AKUL/13/47)funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 874837+2 种基金supported by the Flemish Government(department of Economy,Science and Innovation)through the Regenerative Medicine Crossing Borders(http://www.regmedxb.com)initiativeImages were recorded on a Zeiss LSM 780-SP Mai Tai HP DS(Cell and Tissue Imaging Cluster(CIC),Supported by Hercules AKUL/11/37 and FWO G.0929.15 to Pieter Vanden Berghe,University of Leuvensupported by Interne Fondsen KU Leuven/Internal Funds KU Leuven grant numbers C24M/22/058.
文摘Clinical translation of tissue-engineered advanced therapeutic medicinal products is hindered by a lack of patient-dependent and independent in-process biological quality controls that are reflective of in vivo outcomes.Recent insights into the mechanism of native bone repair highlight a robust path dependence.Organoid-based bottom-up developmental engineering mimics this pathdependence to design personalized living implants scaffold-free,with in-build outcome predictability.Yet,adequate(noninvasive)quality metrics of engineered tissues are lacking.Moreover,insufficient insight into the role of donor variability and biological sex as influencing factors for the mechanism toward bone repair hinders the implementation of such protocols for personalized bone implants.Here,male and female bone-forming organoids were compared to non-bone-forming organoids regarding their extracellular matrix composition,transcriptome,and secreted proteome signatures to directly link in vivo outcomes to quality metrics.As a result,donor variability in bone-forming callus organoids pointed towards two distinct pathways to bone,through either a hypertrophic cartilage or a fibrocartilaginous template.The followed pathway was determined early,as a biological sexdependent activation of distinct progenitor populations.Independent of donor or biological sex,a cartilage-to-bone transition was driven by a common panel of secreted factors that played a role in extracellular matrix remodeling,mineralization,and attraction of vasculature.Hence,the secreted proteome is a source of noninvasive biomarkers that report on biological potency and could be the missing link toward data-driven decision-making in organoid-based bone tissue engineering.
基金Supported by The Russian Scientific Foundation,Moscow,Russian Federation,No.14-15-00112
文摘Inflammation plays an essential role in the development of atherosclerosis. The initiation and growth of atherosclerotic plaques is accompanied by recruitment of inflammatory and precursor cells from the bloodstream and their differentiation towards pro-inflammatory phenotypes. This process is orchestrated by the production of a number of pro-inflammatory cytokines and chemokines. Human arterial intima consists of structurally distinct leaflets, with a proteoglycan-rich layer lying immediately below the endothelial lining. Recent studies reveal the important role of stellate pericyte-like cells(intimal pericytes) populating the proteoglycan-rich layer in the development of atherosclerosis. During the pathologic process, intimal pericytes may participate in the recruitment of inflammatory cells by producing signalling molecules and play a role in the antigen presentation. Intimal pericytes are also involved in lipid accumulation and the formation of foam cells. This review focuses on the role of pericytelike cells in the development of atherosclerotic lesions.
基金Supported by The Fund for Scientific Research,Flanders,Fundamental Clinical Investigatorship,1800209N
文摘Clinical pharmacology aims to predict drug-related effects based on compound and population specific pharmacokinetics(PK, concentration-time), and pharmacodynamics(PD, concentration-effect). Consequently, dosing needs to be based on the physiological characteristics of the individual patient. Pregnancy and early infancy hereby warrant focused assessment. The specific characteristics of both subpopulations will be illustrated based on observations on intravenous(iv) paracetamol PK and PD collected in these specific populations. At delivery, there is a significant higher paracetamol clearance(+ 45%, L/h) when compared to non-pregnant observations. This higher clearance is in part explained by a proportional increase in oxidative metabolite production, but mainly an increase in glucuronidation. When focusing on PD, an association between maternal paracetamol exposure and atopy in infancy and fetal gastroshizis has been reported. In early infancy, paracetamol clearance is significantly lower and mainly depends on size(weight 0.75), while also the distribution volume is higher(L/kg). Reports on hepatic tolerance, haemodynamic stability and impact of bodytemperature have been published while the concentration effect profile for analgesia seems to be similar between neonates and children. Similar to maternal exposure, there are reports on the association with atopy. Studies on the use of paracetamol to close the patent ductus arteriosus are ongoing. At least, these observations provide evidence on the need to study commonly administered anesthetics in such specific subpopulations with specific focus on both population specific PK and PD to further improve patient tailored pharmacotherapy.
基金supported by the Research Foundation—Flanders[G0D3620N and 1133520N]。
文摘Decellularized organs and tissues are emerging within the field ofregenerative medicine to meet the growing demand for organand tissue transplantation. Quality control of these acellular matrices prior to transplantation is of paramount importance to ensure the absence of an adverse reaction. In particular, thoroughevaluation of the DNA content is essential but also poses technical challenges. Therefore, in this study, we compared differentmethods for quantitative and qualitative evaluation of DNA content in native and decellularized skeletal muscle tissue to identifystrengths and weaknesses for each. Histological analysis revealedthat Feulgen staining is more sensitive and robust than the commonly used hematoxylin–eosin and 40,6-diamidino-2-phenylindole staining for detection of remaining nuclear material.Furthermore, gel electrophoresis allowed to identify the quality and length of remaining DNA fragments. The results of the quantitativeanalysis indicated that direct measurement of DNA content in tissue lysates is preferred over silica-based extraction methods, since thelatter resulted in the loss of small DNA fragments during extraction. Moreover, a weight loss correction factor should be implementedto take into account the impact of the decellularization on the extracellular matrix. With regard to the detection method, the resultsrevealed that a fluorescence-based approach is more accurate than the use of UV/VIS absorbance. Through combination of the proposedmethods, it should be possible to achieve a more standardized evaluation of novel acellular matrices in terms of DNA content and toenhance the predictability of clinical success.
基金Supported by The Fund for Scientific Research,Flanders(Fundamental Clinical Investigatorship 1800209N)
文摘Drugs are very strong tools used to improve outcome in neonates. Despite this fact and in contrast to tailored perfusion equipment, incubators or ventilators for neonates, we still commonly use drug formulations initially developed for adults. We would like to make the point that drug formulations given to neonates need to be tailored for this age group. Besides the obvious need to search for active compounds that take the pathophysiology of the newborn into account, this includes the dosage and formulation. The dosage or concentration should facilitate the administration of low amounts and be flexible since clearance is lower in neonates with additional extensive between-individual variability. Formulations need to be tailored for dosage variability in the low ranges and also to the clinical characteristics of neonates. A specific focus of interest during neonatal drug development therefore is a need to quantify and limit excipient exposure based on the available knowledge of their safety or toxicity. Until such tailored vials and formulations become available, compounding practices for drug formulations in neonates should be evaluated to guarantee the correct dosing, product stability and safety.
基金supported by EU-FP7 CARE-MI,FWO(#G060612N,#G0A8813N,#G088715N),Opening the Future Campaign EJJ-OPTFUT-02010,and Rondoufonds voor Duchenne Onderzoek.D.C.has been supported by University of Turin.M.Q.is supported by FWO(Postdoctoral Fellowship#1263314N and Travel Grant#V448715N)and AFM(Trampoline Grant#18373).The D.H.lab is supported by a start-up grant of Erasmus MC.We also acknowledge infrastructural funding by the InfraMouse Grant from the Hercules Foundation(ZW09-03,to D.H.and A.Z.)and FWO-V G.0542.13(to A.Z.and D.H.).M.S.,D.H.,and A.Z.are supported by KU Leuven Research Council funding(OT-09/053 and GOA-11/012),the Belgian Agency for Science Policy(Belspo)network IUAPVII-07 DevRepair.
文摘Mesoangioblasts(MABs)are vessel-associated stem cells that express pericyte marker genes and participate in skeletal muscle regeneration.Molecular circuits that regulate the myogenic commitment of MABs are still poorly characterized.The critical role of bone morphogenetic protein(BMP)signalling during proliferation and differentiation of adult myogenic precursors,such as satellite cells,has recently been established.Weevaluated whether BMP signalling impacts on the myogenic potential of embryonic and adult MABs both in vitro and in vivo.Addition of BMP inhibited MAB myogenic differentiation,whereas interference with the interactions between BMPs and receptor complexes induced differentiation.Similarly,siRNA-mediated knockdown of Smad8 in Smad1/5-null MABs or inhibition of SMAD1/5/8 phosphorylation with Dorsomorphin(DM)also improved myogenic differentiation,demonstrating a novel role of SMAD8.Moreover,using a transgenic mouse model of Smad8 deletion,we demonstrated that the absence of SMAD8 protein improved MAB myogenic differentiation.Furthermore,once injected into a-Sarcoglycan(Sgca)-null muscles,DM-treated MABs were more efficacious to restore a-sarcoglycan(aSG)protein levels and re-establish functional muscle properties.Similarly,in acute muscle damage,DM-treated MABs displayed a better myogenic potential compared with BMP-treated and untreated cells.Finally,SMADs also control the myogenic commitment of human MABs(hMABs).BMP signalling antagonists are therefore novel candidates to improve the therapeutic effects of hMABs.
